proc.c revision 496ad9aa8ef448058e36ca7a787c61f2e63f0f54 
1/*
2 *  ISA Plug & Play support
3 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *   This program is free software; you can redistribute it and/or modify
6 *   it under the terms of the GNU General Public License as published by
7 *   the Free Software Foundation; either version 2 of the License, or
8 *   (at your option) any later version.
9 *
10 *   This program is distributed in the hope that it will be useful,
11 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
12 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 *   GNU General Public License for more details.
14 *
15 *   You should have received a copy of the GNU General Public License
16 *   along with this program; if not, write to the Free Software
17 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20#include <linux/module.h>
21#include <linux/isapnp.h>
22#include <linux/proc_fs.h>
23#include <linux/init.h>
24#include <asm/uaccess.h>
25
26extern struct pnp_protocol isapnp_protocol;
27
28static struct proc_dir_entry *isapnp_proc_bus_dir = NULL;
29
30static loff_t isapnp_proc_bus_lseek(struct file *file, loff_t off, int whence)
31{
32	loff_t new = -1;
33	struct inode *inode = file_inode(file);
34
35	mutex_lock(&inode->i_mutex);
36	switch (whence) {
37	case 0:
38		new = off;
39		break;
40	case 1:
41		new = file->f_pos + off;
42		break;
43	case 2:
44		new = 256 + off;
45		break;
46	}
47	if (new < 0 || new > 256)
48		new = -EINVAL;
49	else
50		file->f_pos = new;
51	mutex_unlock(&inode->i_mutex);
52	return new;
53}
54
55static ssize_t isapnp_proc_bus_read(struct file *file, char __user * buf,
56				    size_t nbytes, loff_t * ppos)
57{
58	struct inode *ino = file_inode(file);
59	struct proc_dir_entry *dp = PDE(ino);
60	struct pnp_dev *dev = dp->data;
61	int pos = *ppos;
62	int cnt, size = 256;
63
64	if (pos >= size)
65		return 0;
66	if (nbytes >= size)
67		nbytes = size;
68	if (pos + nbytes > size)
69		nbytes = size - pos;
70	cnt = nbytes;
71
72	if (!access_ok(VERIFY_WRITE, buf, cnt))
73		return -EINVAL;
74
75	isapnp_cfg_begin(dev->card->number, dev->number);
76	for (; pos < 256 && cnt > 0; pos++, buf++, cnt--) {
77		unsigned char val;
78		val = isapnp_read_byte(pos);
79		__put_user(val, buf);
80	}
81	isapnp_cfg_end();
82
83	*ppos = pos;
84	return nbytes;
85}
86
87static const struct file_operations isapnp_proc_bus_file_operations = {
88	.owner	= THIS_MODULE,
89	.llseek = isapnp_proc_bus_lseek,
90	.read = isapnp_proc_bus_read,
91};
92
93static int isapnp_proc_attach_device(struct pnp_dev *dev)
94{
95	struct pnp_card *bus = dev->card;
96	struct proc_dir_entry *de, *e;
97	char name[16];
98
99	if (!(de = bus->procdir)) {
100		sprintf(name, "%02x", bus->number);
101		de = bus->procdir = proc_mkdir(name, isapnp_proc_bus_dir);
102		if (!de)
103			return -ENOMEM;
104	}
105	sprintf(name, "%02x", dev->number);
106	e = dev->procent = proc_create_data(name, S_IFREG | S_IRUGO, de,
107			&isapnp_proc_bus_file_operations, dev);
108	if (!e)
109		return -ENOMEM;
110	e->size = 256;
111	return 0;
112}
113
114int __init isapnp_proc_init(void)
115{
116	struct pnp_dev *dev;
117
118	isapnp_proc_bus_dir = proc_mkdir("bus/isapnp", NULL);
119	protocol_for_each_dev(&isapnp_protocol, dev) {
120		isapnp_proc_attach_device(dev);
121	}
122	return 0;
123}
124